package servlet;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Calendar;
import java.util.GregorianCalendar;

public class AutoRefreshServlet extends HttpServlet {
    // 处理 GET 方法请求的方法
    public void doGet(HttpServletRequest request,
                      HttpServletResponse response)
            throws ServletException, IOException {
        // 设置刷新自动加载的事件间隔为 5 秒
        response.setCharacterEncoding("UTF-8");
        response.setIntHeader("Refresh", 5);

        // 设置响应内容类型
        response.setContentType("text/html;utf8");

        // 获取当前的时间
        Calendar calendar = new GregorianCalendar();
        String am_pm;
        int hour = calendar.get(Calendar.HOUR);
        int minute = calendar.get(Calendar.MINUTE);
        int second = calendar.get(Calendar.SECOND);
        if (calendar.get(Calendar.AM_PM) == 0)
            am_pm = "AM";
        else
            am_pm = "PM";

        String CT = hour + ":" + minute + ":" + second + " " + am_pm;

        PrintWriter out = response.getWriter();
        String title = "使用 Servlet 自动刷新页面";
        String docType =
                "<!doctype html public \"-//w3c//dtd html 4.0 " + "transitional//en\">\n";
        out.println(docType +
                "<html>\n" +
                "<head><title>" + title + "</title></head>\n" +
                "<body bgcolor=\"#f0f0f0\">\n" +
                "<h1 align=\"center\">" + title + "</h1>\n" +
                "<p>当前时间是：" + CT + "</p>\n");
    }
}
